Planning for the weather is a good way to make your trip to Colby relaxing and enjoyable, especially when you’re splurging. The hottest months are usually July and August with an average temp of 76°F, while the coldest months are January and February with an average of 36°F. The snowiest months in Colby are January, December, March, and November, with each month seeing an average of 6 inches of snowfall.